• 한국환경생태학회지
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• 제16권1호
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• pp.46-54
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• 2002

천안시내에 식재된 가로수의 건강도를 진단하기 위하여 몇 가지 생리적 특성을 측정하고, 형성층 전기저항치와 생리적 특성들간의 관계를 밝히고자 하였다. 은행나무, 벚나무, 버드나무를 대상수종으로 선정하였고. 7월에 대상 수종의 하부 토양을 채취하여 탈수소효소 활성을 분석하였으며, 수관의 잎은 엽록소 함량, 질산환원 효소, 항산화효소(SOD) 활성을 분석하는데 이용하였다. 수목의 형성층 전기전항치는 5월, 7월, 9월에 측정하였다. 토양의 탈수소효소 활성은 도심지역에서 낮은 값을 나타내 토양 오염도를 반영하였으며. 엽록소 함량은 동서대로에 식재된 벚나무가 가장 낮았다. 은행나무의 질산환원효소 활성은 다른 수종보다 높았으며 도심지역에서 높은 활성을 나타냈다. 또한 항산화효소인 SOD 활성은 도심에서 낮았다. 동서대로의 벚나무는 형성층 전기저항치가 지속적으로 상승하여 활력을 상실하였음을 보여주었다. 형성층 전기저항치는 질산환원효소($r^2$=-0.566) 및 SOD활성($r^2$=0.579)과 상관을 보임으로써 수목의 건강도 및 생리적 건강 상태를 진단하는데 유용할 것으로 판단되었다.

• 농업과학연구
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• 제45권3호
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• pp.365-378
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• 2018

Anthracnose caused by Colletotrichum gloeosporioides, which is one of the major diseases of red dates, causes severe damages in jujube (Zizyphus jujuba Miller) production in Korea. This study was done to evaluate the inhibition of anthracnose occurrence and pathogen growth by the treatment of environment-friendly materials such as a Bordeaux mixture and loess-sulfur mixture and by defense-response signaling in jujube. The in vitro test of the environment-friendly materials and signaling molecules that were routinely applied did not exhibit any antifungal activities against the pathogen for jujube anthracnose. The Bordeaux mixture and loess-sulfur mixture at a two-fold concentration showed inhibition zones that were 16.0 and 20.3 mm in diameter, respectively. In the pathogen inoculation test with detached jujube tree leaves, while treatment with the environment-friendly materials diluted by half showed no inhibition of lesion development, they did show inhibition of lesion development when they were routinely applied to the leaves. In detached jujube fruits inoculated with the pathogen, better suppressive effects by the treatment of the environment-friendly materials were seen in the fruits at a young stage rather than in the ripening stage. The in vivo test with jujube trees in pots showed that the treatment of salicylic acid (1 mM) resulted in the best suppressive effects against lesion development. The results suggest that it is possible to manage the incidence of anthracnose by the treatment of environment-friendly materials such as the Bordeaux and loess-sulfur mixtures and signaling chemicals such as ethephon, hydrogen peroxide, methyl jasmonate, and salicylic acid in jujube trees and fruits. Consequently, these findings suggest that environment-friendly materials and defense response signaling molecules could be used as suitable candidates for sustainable agrochemicals to manage anthracnose in jujube production.

• 한국산림과학회지
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• 제87권1호
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• pp.50-56
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• 1998

오존에 약(弱)하거나 저항성(抵抗性)을 가지는 포플러 개체(個體)를 선발(選拔)하기 위해서 36개의 잡종(雜種)포플러 클론을 오존에 노출(露出)시켰다. Open-top chamber를 이용(利用)하여 하루에 6-8시간, 3개월 동안 90-115ppb의 농도(濃度)로 오존을 노출시켰다. 수고(樹高), 직경(直徑), 엽수(葉數), 물질생산량(物質生産量), root/shoot비율(比率), 낙엽률(落葉率), 기공반응(氣孔反應) 조사(調査)하였다. 수고, 직경, 엽수, 물질생산량, root/shoot비율, 기공 conductance는 오존 때문에 감소(減少)하였고, 낙엽률은 증가(增加)하였다. 이 연구에서는 기공 conductance와 물질생산량과의 관계(關係)는 아주 낮게 나타났다. 오존환경(環境)에 대해서 저항성을 갖는 것은 기공(氣孔)의 개폐(開閉)와 항상(恒常) 관계(關係)가 있는 것은 아니라고 사료(思料)되며, 아마도 생화학적(生化學的)이고 생리적(生理的)인 다른 요인(要因)에 대(對)한 연구(硏究)가 포플러 클론이 갖는 저항성을 이해(理解)하는데 도움이 될 것이다.

• 한국작물학회지
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• 제45권2호
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• pp.143-149
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• 2000

From the soils of soybean fields in Cotton Branch Station (CBS) and Pine Tree Station (PTS), Arkansas, USA, various single spore isloates of sudden death syndrome (SDS) pathogen were obtained on modified Nash ＆ Snyder's medium (MNSM) with dilution plating technique and transferred to potato dextrose agar (PDA) medium to identify the cultural colony shape. The colony shapes of these isolates resembled F. solani isolate 171 which was white and chalky shaped on MNSM and most of them had unique form of morphology which produced white margin and blue center colony on PDA. Although, some of these isolates had more dark blue or showed slightly different color, all isolates that were selected randomly for green-house inoculation assay produced typical foliar symptoms on leaves of soybean, Hartz 6686. To determine the genetic differences among the isolates, mitochondrial DNA restriction fragment length polymorphism (RFLP) was conducted with fourty isolates from both fields, using mtDNA probes, 2U18 and 4U40, derived from Colletotrichum orbiculare. We obtained distinctive RFLPs in each treatment of restriction enzyme, EcoRI and HaeⅢ. Isolates, 11-2-5 and 14-3-1-1, from CBS and isolates, 104-3-1-2 and 701-1-5-1, from PTS showed different band patterns from 171 in both or in either treatment of restriction enzymes. Even if some of these isolates showed heterogeneous, they were more closer to 171 than PN603. And, also, rest of the thirty-six isolates had exactly same polymorphisms as 171 in each treatment of restriction enzyme. Although, some of the isolates showed the different morphological shape on PDA and slightly different band patterns on RFLPs, all of the isolates selected on MNSM due to their distinctive colony shape from other fungi produced the typical foliar symptoms on soybean leaves in greenhouse inoculation assay. It might be suggested that these isolates were not genetically different from check isolate 171 and they were unique strain of F. solani.

• 한국식품저장유통학회지
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• 제17권4호
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• pp.466-470
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• 2010

본 연구는 유기질 멀칭에 의해 배 '신고' 과실 품질에 미치는 영향을 알아보기 위해서 수행되었다. 볏짚 멀칭은 엽중 칼륨, 마그네슘, 칼슘 함량을 높였지만 모두 적정농도 이하의 수준을 나타냈다. 과실의 경도는 참나무껍질에 의해 증가하였고 당도는 참나무껍질과 볏짚에 의해 증가하였다. 참나무 껍질은 가장 높은 당산비를 보였고 진한 붉은 계열의 과피색을 착색시켰다. 과실의 칼륨은 볏짚에서 칼슘은 참나무껍질에서 가장 높았으나, 두 무기성분간의 과실 내 흡수에 있어서 길항작용이 있었던 것으로 판단된다. 일반적으로, 과실 품질을 향상시켰던 유기질 멀칭 자재인 참나무껍질과 볏짚은 석세포 함량을 감소시켰고 유기질이 투입되지 않는 폴리에틸렌은 대조구와 비슷한 석세포 함량을 보였다. 따라서 과원 내 유기질이 투입된 멀칭 시용은 과실 품질을 부분적으로 향상시켰고 과실의 씹힘성을 저해하는 석세포를 감소시켜서 과실의 품질 개선에 기여한 것으로 판단된다.

• 셀메드
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• 제4권2호
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• pp.11.1-11.6
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• 2014

Cinnamomum zeylanicum (C. zeylanicum) is a tropical evergreen tree of Lauraceae family. It is one of the oldest culinary spices known and used traditionally in many cultures for centuries. In addition to its culinary uses, cinnamon also possesses as a folk remedy of many health disease condition including analgesic, antiseptic, antispasmodic, aphrodisiac, astringent, carminative, haemostatic, insecticidal, and parasiticide and memory enhancing property. This study was aimed to assess the acetylcholinesterase and butyrylcholinesterase inhibitory activity of standardized methanol extract of the C. zeylanicum. Gas chromatography - mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC) analysis were done to identify the presence of eugenol as chemical component and support the neuroprotective activity in the extract. Anticholinesterase inhibitory activity of crude methanol extract of C. zeylanicum leaves and cinnamon oil were evaluated by 96-well microtiter plate assay and thin layer chromatography bioassay detection methods. This study revealed that cinnamon oil ($IC_{50}:45.88{\pm}1.94{\mu}g/ml$) has better anticholinesterase activity than methanol extract ($IC_{50}:77.78{\pm}0.03{\mu}g/ml$). In HPLC analysis, retention time of eugenol in cinnamon oil was found to be 15.81 min which was comparable with the retention time (15.99 min) of the reference standard, eugenol. Seven chemical compounds were identified by GC-MS analysis, in which eugenol as an important phytoconstituents. Thus the phytochemicals from C. zeylanicum methanol leaves extract could be developed as potential source of anticholinesterase activity, with particular benefit in the symptomatic treatment of Alzheimer's disease.

• 농업과학연구
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• 제46권4호
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• pp.737-754
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• 2019

Peaches have soft tissues compared to other fruits and are vulnerable to softness, wounds, and loss of marketability due to the weak fruit hardness after harvest. It is necessary to develop a technology to improve the shelf-life of the fruit to expand the distribution of peaches. Calcium compounds and chitosan have an important role in improving the shelf-life of fruit by maintaining the hardness and reducing the respiration rate in peach fruits. In this study, to select useful compounds to improve the shelf-life of peaches, calcium citrate, calcium chloride, calcium nitrate, GH-Ca, OS-Ca, chitosan, and chitosan dissolved in calcium chloride were sprayed onto peach trees. The characteristics of the harvested fruits were investigated after the 'Kumhong' and 'Madoka' peach tree treatments. The hardness of the fruit was kept the highest with the combined treatment and remained high with the calcium citrate, chitosan and calcium nitrate treatments. Ethylene production and respiration were effectively inhibited by the GH-Ca and chitosan treatments. There was no significant difference in soluble solids content and acidity among the fruits treated with the chemicals. The coloration of the fruit skin was not delayed by the calcium and chitosan chemical treatments. Calcium compounds were increased in the fruits and leaves of the peach trees treated with the chemicals compared to the untreated ones. These results suggest that the calcium treatment extended the shelf-life by increasing the calcium content in the leaves and fruits of the peach trees.

• 한국식품과학회지
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• 제27권2호
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• pp.257-263
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• 1995

As a primary step to develop natural preservative for extending the shelf-life of kimchi, the effect of 102 edible plants, 21 antimicrobial agents and related compounds on kimchi fermentation was studied. Among 42 oriental medicinal plants tested, Baical skullcap and Assam indigo were found to be highly effective for maintaining the fresh state of kimchi. Although Bugbane, Red mangolia, Bushy sophora, Szechuan pepper, Chinese quince and Scisandre significantly inhibit the growth of Lactobacilli, their effect was not high enough to be used as raw materials for kimchi preservative. When the effect of 32 herbs and spices was tested, peppermint, cinnamon, lemon balm, clove, hop, rosemary, sage, horseradish and thyme showed high antimicrobial activity against kimchi microorganisms. Among them, the effect of clove ranked top. When it was added to fresh kimchi, initial cfu value ($2.4{\times}10^{6}cfu/g$) changed little even after 2 day's fermentation ($2.6{\times}10^{6}cfu/g$). Sensory test was not a good criteria to evaluate the effect of herbs and spices, since their highly specific flavors affected the taste of kimchies. Twenty eight fruits, vegetables and related plants were tested, but only leaves of pine tree, persimmon and oak leaves showed a significant bactericidal effect, finally contributing to the storage of kimchi. In addition, when 21 natural preservatives and other compounds were added individually to fresh kimchi, nisin and caffeic acid could inhibit fermentation.

• 한국약용작물학회지
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• 제7권1호
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• pp.22-26
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• 1999

오갈피나무의 묘목(苗木)을 실생(實生)으로 대량생산 체계를 확립하기 위한 일환으로 하우스를 이용한 육묘이식재배(育苗移植栽培) 시험을 수행하면서 출아율(出芽率), 활착률(活着率), 득묘율(得苗率) 및 생육특성(生育特性)을 조사하였다. 출아율(出芽率)은 하우스내 파종에서 약 90%의 수치를 보였으나 노지직파(露地直播)에서는 약 40%로 나타났으며, 이식할 때 본엽수(本葉數)에 따른 활착률(活着率)은 본엽 $2{\sim}3$매에서 100%이었으나 그보다 적거나 많으면 감소하였다. 그리고 이식시기에 따른 활착률(活着率)은 4월 하순부터, 5월 초순에는 100%로 나타났으나 그보다 이르거나 늦으면 감소하였다. 또한 득묘율(得苗率), 수고(樹高), 근장(根長) 및 생체중(生體重)은 노지직파재배구(露地直播栽培區)보다 육묘이식재배구(育苗移植栽培區)에서 모두 높은 수치를 보였다.

• The Plant Pathology Journal
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• 제39권1호
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• pp.88-107
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• 2023

In the present investigation, bacterial isolates from infected apple trees causing apple canker during winter were studied in the northern Gyeongbuk Province, Korea. The pathogen was identified as Pseudomonas syringae pv. syringae (Pss) through various physiological and biochemical characterization assays such as BIOLOG, gas chromatography of fatty acid methyl esters, and 16S rRNA. Bioassays for the production of phytotoxins were positive for syringopeptin and syringomycin against Bacillus megaterium and Geotrichum candidum, respectively. The polymerase chain reaction (PCR) method enabled the detection of toxin-producing genes, syrB1, and sypB in Pss. The differentiation of strains was performed using LOPAT and GATTa tests. Pss further exhibited ice nucleation activity (INA) at a temperature of -0.7℃, indicating an INA⁺ bacterium. The ice-nucleating temperature was -4.7℃ for a non-treated control (sterilized distilled water), whereas it was -9.6℃ for an INA^- bacterium Escherichia coli TOP10. These methods detected pathogenic strains from apple orchards. Pss might exist in an apple tree during ice injury, and it secretes a toxin that makes leaves yellow and cause canker symptoms. Until now, Korea has not developed antibiotics targeting Pss. Therefore, it is necessary to develop effective disease control to combat Pss in apple orchards. Pathogenicity test on apple leaves and stems showed canker symptoms. The pathogenic bacterium was re-isolated from symptomatic plant tissue and confirmed as original isolates by 16S rRNA. Repetitive element sequence-based PCR and enterobacterial repetitive intergenic consensus PCR primers revealed different genetic profiles within P. syringae pathovars. High antibiotic susceptibility results showed the misreading of mRNA caused by streptomycin and oxytetracycline.